Haidt’s book proposes that both Republicans and Democrats are interested in equality. Republicans are more motivated by equality of opportunity, while Democrats are more motivated by equality of outcomes. And since all of us think of ourselves as moral, those in the other political party, by default, are “immoral,” thus much easier for us to demonize.

I was thinking about this sense of morality when I read a Lifehacker article by Adam Dachis on “How to Deal With People Who Cut In Line.” I suspect that, for most of us, witnessing someone cut in line is the kind of moral transgression we’re more likely to see over the course of a day.

And as more of us use our smartphones to “check in” on Foursquare while waiting in line for our morning latte, I have to wonder: are we more likely or less likely to notice line-cutters?

Even though our phones are a source of distraction as much as information, I suspect that the “fairness” switch in our heads stays on, and we would still be likely to catch on if someone cuts in front of us in line.

Which asks the question: if we witness someone cutting line, what are we going to do about it?

More of us, it seems, are taking the opportunity to enforce social norms with a bit of “social shaming.” Blogger Chirag Mehta shares the story of Joshua Kaufman, whose MacBook was stolen one day. The laptop already had tracking software installed, just in case it was stolen, so Kaufman was able to track the laptop’s location and use the software to take webcam pictures of the thief. He shared the story, along with the pictures, via his Twitter feed and Facebook page, and the thief was caught.

So the next time I’m standing line, smartphone at the hip, and someone cuts in line, should I quickdraw, Tweeting pics and text about the immoral line-cutter? Adam Dachis would say “not so fast.”

His advice for when this happens:

1) Analyze the line.

Maybe the line-cutter just got confused and thought it was a rugby scrum instead of a polite queue, or maybe the instructions are confusing. Maybe there is no line at all.

2) Resist the urge to get angry.

If you show off your bad manners and scream at them, it makes you look like a loser.

3) Ask someone else if they saw what you saw, and if they agree, that’s the moment to politely confront the cutter and motion them to the back of the line.

Social shaming can be a very big hammer, so try not to use it if you’re confronted with a very small nail. Once you tweet and post a rant, it cannot easily be taken back. Besides, like all good moral beings, your friends may be motivated to punish your bad behavior with a little social shaming of their own.